https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101326
Andrew Pinski <pinskia at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Last reconfirmed| |2021-07-05 Severity|normal |enhancement Status|UNCONFIRMED |NEW Ever confirmed|0 |1 --- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> --- Take: struct g { unsigned long b; }; struct a { struct g g1; unsigned char c; }; static inline void h(struct g *a) { a->b = 0; } static inline void j(struct a *a) { h(&a->g1); a->c = 1; } struct a f(void) { struct a a; j(&a); return a; } ---- CUT ---- It works, I suspect in the case of std::optional, std::optional is marked as BLKmode rather than TImode as the struct is marked as "ADDRESSABLE".